From: Andrew Pinski <apin...@marvell.com>
There is some re-association code in fold_binary which conflicts with
this optimization due keeping around some "constants" which are not
INTEGER_CST (1 << -1) so we end up in an infinite loop because of that.
So we need to limit this case to GIMPLE level only.
OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
PR tree-optimization/103314
gcc/ChangeLog:
* match.pd ((type) X op CST): Restrict the equal
TYPE_PRECISION case to GIMPLE only.
gcc/testsuite/ChangeLog:
* gcc.c-torture/compile/pr103314-1.c: New test.
---
gcc/match.pd | 6 +++++-
gcc/testsuite/gcc.c-torture/compile/pr103314-1.c | 6 ++++++
2 files changed, 11 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.c-torture/compile/pr103314-1.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 4dc66fb47f2..24a84e3b504 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1619,7 +1619,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
after hoisting the conversion the operation will be narrower.
It is also a good if the conversion is a nop as moves the
conversion to one side; allowing for combining of the
conversions. */
- TYPE_PRECISION (TREE_TYPE (@0)) <= TYPE_PRECISION (type)
+ TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
+ /* The conversion check for being a nop can only be done at the
gimple
+ level as fold_binary has some re-association code which can
conflict
+ with this if there is a "constant" which is not a full
INTEGER_CST. */
+ || (GIMPLE && TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION
(type))
/* It's also a good idea if the conversion is to a non-integer
mode. */
|| GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr103314-1.c
b/gcc/testsuite/gcc.c-torture/compile/pr103314-1.c
new file mode 100644
index 00000000000..f4a63130421
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr103314-1.c
@@ -0,0 +1,6 @@
+/* { dg-options "" } */
+int main() {
+ int t = 1;
+ unsigned c = 0, d1 = t ? 1 ^ c ^ 1 >> (-1) : 0; /* { dg-warning "is
negative" } */
+ return d1;
+}
--
2.17.1
